SEARCH · PubMed Health

Results for “First Pregnancy Intervals”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 289 records · Page 16Linked to original sources

PubMed2002

Occurrence of omphalocele in relation to maternal multivitamin use: a population-based study.

OBJECTIVE: We evaluated the association between mothers' use of multivitamin supplements and their infants' risk for omphalocele, a congenital anomaly of the abdominal wall. Omphalocele can occur in certain multiple congenital anomaly patterns with neural tube defects, for which a protective effect of multivitamins with folic acid has been demonstrated. METHODS: We used data from a population-based case-control study of infants born from 1968-1980 to mothers residing in metropolitan Atlanta. Case-infants with nonsyndromic omphalocele (n = 72) were actively ascertained from multiple sources. Control-infants (n = 3029), without birth defects, were selected from birth certificates by stratified random sampling. RESULTS: Compared with no use in the periconceptional period, periconceptional use of multivitamin supplements (regular use from 3 months before pregnancy through the first trimester of pregnancy) was associated with an odds ratio for nonsyndromic omphalocele of 0.4 (95% confidence interval [CI]: 0.2-1.0). For the subset comprising omphalocele alone or with selected midline defects (neural tube defects, hypospadias, and bladder/cloacal exstrophy), the odds ratio was 0.3 (95% CI: 0.1-0.9). These estimates were similar when the reference group also included women who began using multivitamins late in pregnancy (during the second or third month of pregnancy). The small number of participants limited the precision of subgroup analyses and translated into wide confidence intervals that included unity. CONCLUSIONS: Periconceptional multivitamin use was associated with a 60% reduction in the risk for nonsyndromic omphalocele. These findings await replication from additional studies to confirm the findings, generate more precise estimates, and detail possible mechanisms of actions.

Case-Control Studies↗

PubMed1989

Dietary folate as a risk factor for neural-tube defects: evidence from a case-control study in Western Australia.

A population-based case-control study was conducted to test the hypothesis that the risk of the occurrence of neural-tube defects in infants with no other birth defects (isolated neural-tube defects) is associated inversely with the maternal dietary intake of free and/or total folate in early pregnancy. Information was collected from the mothers of 77 case subjects with isolated neural-tube defects who were born in Western Australia from 1982 to 1984, from the mothers of 77 control subjects with birth defects other than neural-tube defects (control group 1) and from the mothers of 154 control subjects with no birth defects (control group 2). The case and control subjects were matched individually by the date of the mother's last menstrual period. Odds ratios were adjusted for a number of potentially-confounding variables, such as the country of birth of the parents, paternal social class, previous pregnancy outcome, interval between index and previous pregnancy and pregnancy order. Crude and adjusted odds ratios showed a protective effect of an increasing intake of free folate in the first six weeks of pregnancy. Adjusted odds ratios, with reference to the lowest quartile of intake, (and their 95% confidence intervals) were 0.72 (0.25-2.08), 0.37 (0.11-1.23) and 0.31 (0.10-0.97) for quartiles 2-4 when control group 1 was used, and 0.44 (0.17-1.13), 0.34 (0.13-0.90) and 0.16 (0.06-0.49) when control group 2 was used. Similar, but weaker, trends were seen when total folate intake was the exposure variable. These findings support the hypothesis that the dietary intake of folate in early pregnancy protects against the occurrence of isolated neural-tube defects in infants. Measures of postpartum dietary folate and of postpartum serum and red-cell folate levels showed no association with the occurrence of neural-tube defects in infants.

Diet↗

PubMed2004

Reproductive factors and extreme levels of maternal serum alpha-fetoprotein: a population-based study.

BACKGROUND: Levels of maternal alpha-fetoprotein (AFP) are increased during multiple gestations and preeclampsia but little is known regarding AFP levels in relation to other reproductive factors. Consequently, the objective of this work was to describe the possible relationship between AFP levels during pregnancy and maternal age at birth, maternal age at first birth, parity, time since previous birth and gender of the offspring. METHODS: Based on national registries we obtained the reproductive history on a population-based cohort of 44 227 women who had serum AFP levels determined in gestational weeks 14-21 and whose present and previous pregnancies resulted in live-born singletons. RESULTS: Many previous births and an interval of less than 2 years since last birth were significantly associated with extremely low levels of AFP in the mother. However, age at first birth and age at present pregnancy did not influence the AFP level. Women who gave birth to a girl had AFP levels that were 5%[95% confidence interval (CI) 4-6%] lower than those of women who had a boy. Adjustment for birthweight did not significantly affect the estimate. CONCLUSIONS: Low serum AFP levels in pregnancy are significantly correlated with high parity and with a short interval between births. The significantly lower levels of AFP in women who gave birth to girls could indicate a possible gender-specific regulatory mechanism.

Adolescent↗

PubMed1994

Risk of breast cancer in relation to the interval since last full term pregnancy.

OBJECTIVE: To examine whether the risk of breast cancer is increased by a recent term pregnancy. DESIGN: Population based case-control study. SETTING: Eight areas in the United States. SUBJECTS: Cases were 2279 multiparous women residents of the eight areas aged 25-49 who were diagnosed as having breast cancer during 1980-2. Controls were 2357 multiparous women selected from the same areas by random digit dialing. MAIN OUTCOME MEASURE: Relative risk of developing breast cancer according to the time interval since last full term pregnancy. RESULTS: The distribution of intervals since the last term pregnancy was similar in cases and controls. Adjusted for age, parity, and age at first term pregnancy, the odds ratios observed for categories of years since the last full term pregnancy were: 0-2 years, odds ratio 1.16 (95% confidence interval 0.84 to 1.59); 3-6 years, odds ratio 1.21 (0.95 to 1.54); 7-9 years, odds ratio 1.04 (0.84 to 1.38); > or = 10 years, odds ratio 1.00 (reference). CONCLUSIONS: Among multiparous women aged 25-49 years there was no association between the risk of breast cancer and the time interval since the last full term pregnancy.

Adult↗

PubMed2006

Risk of stillbirth in relation to maternal haemoglobin concentration during pregnancy.

The authors determined the association between maternal haemoglobin concentration measured at <28 weeks' gestation and late fetal death at >or=28 weeks' gestation (stillbirth). Data were derived from the National Maternal and Infant Health Survey--a nationally representative survey of US deliveries in 1988. Analysis was restricted to women with a singleton live birth (n = 4,199) or a stillbirth (n = 1,375) for whom maternal prenatal care, haemoglobin, smoking status and gestational age data were available. Haemoglobin concentrations during first and second trimesters, respectively, were classified as mild (10.0 to <11.0 and 9.5 to <10.5 g dL(-1)) or moderate (9.0 to <10.0 and 8.5 to <9.5 g dL(-1)) anaemia, or high haemoglobin (>or=14.6 g dL(-1) in either trimester). Hazard ratios (HR) and 95% confidence intervals (CI) for stillbirth were derived from discrete proportional hazards regression models after adjusting for confounders. Stillbirth was not associated with mild anaemia or high haemoglobin in either the first or second trimester of pregnancy. Moderate anaemia measured before 28 weeks' gestation was significantly associated with an increased risk of stillbirth among non-black women (adjusted HR: 4.4; 95% CI: 1.02, 19.01). Moderate anaemia was not associated with stillbirths among black women. Further investigation regarding causal mechanisms for this association is warranted.

Adult↗

PubMed1984

Epidemiology of frontoethmoidal encephalomeningocoele in Burma.

One hundred and thirty nine patients suffering from encephalomeningocoele and myelomeningocoele who had attended the neurosurgical outpatients department of the Rangoon People's Hospital were interviewed. A predominance of frontal encephalomeningocoele was found; a low proportion of these patients had been conceived in the cold season and an increased interval separated the index patients from the previous full term pregnancy of their mothers; no first degree relatives were affected. It is suggested that an environmental factor is implicated in the developmental aetiology.

Adolescent↗

PubMed1993

Endocrine changes and luteal morphology during pregnancy in muskoxen (Ovibos moschatus).

Progesterone, oestradiol and oestrone were measured in plasma from four captive muskoxen during three consecutive pregnancies (1983-1984, 1984-1985 and 1985-1986). Jugular blood samples were collected weekly (1983) or on an alternating 3:4 day schedule (1984-1986) during the first 12-15 weeks and last 6-10 weeks of pregnancy. Sampling during mid-pregnancy was at intervals of 2 weeks (1983 and 1985) or 1 week (1986). Duration of gestation was about 34 weeks (235 +/- 4 (SD) days (n = 10), range 230-242 days). Progesterone remained at concentrations similar to those found during the luteal phase of the oestrous cycle for the first 10-12 weeks (mean +/- SEM 1.6 +/- 0.1 ng ml-1) after which it rose to a peak (mean 5.5 +/- 0.65 ng ml-1) between weeks 12 and 20. In all ten pregnancies progesterone concentrations declined dramatically between weeks 20 and 22 to luteal phase values where they remained until parturition. The decline was accompanied by an increase in oestradiol and oestrone concentrations which reached mean peak values of 199.23 +/- 87.23 pg ml-1 and 980.48 +/- 203.91 pg ml-1, respectively. Corpora lutea collected from wild muskoxen between 45 and 80 days gestation all showed histological evidence of regression, while corpora lutea from mid-gestation (112-125 days) were in advanced stages of involution. Repeated ovarian ultrasonography of captive muskoxen during the first 100 days of pregnancy confirmed these findings. The unusual, early regression of the corpus luteum of pregnancy indicates that progesterone and oestrogen of mid- and late pregnancy are probably of placental origin.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1995

Agricultural work during pregnancy and selected structural malformations in Finland.

We studied the relation between birth defects and maternal agricultural work in a nationwide time- and area-matched case-referent series of 1,306 pairs of infants (581 orofacial clefts, 365 central nervous system defects, 360 skeletal defects) obtained through the Finnish Register of Congenital Malformations. We supplemented the Register data, including the mothers' latest and previous pregnancies, diseases, consumption of drugs and alcohol, smoking habits, and the like, with detailed interviews on the mothers' work conditions. When all of the birth defects were pooled and agricultural work was compared with nonagricultural work in the first trimester of pregnancy, the adjusted odds ratio was 1.4 [95% confidence interval (CI) = 0.9-2.0]. For orofacial clefts, the corresponding odds ratio was 1.9 (95% CI = 1.1-3.5). An industrial hygienist's blinded assessment indicated that seven mothers of infants with orofacial clefts and three reference mothers had been exposed to pesticides in agricultural work; the adjusted odds ratio for work with pesticide exposure, when compared with unexposed agricultural work, was 1.9 (95% CI = 0.4-8.3). Exposure to solvents did not explain the observed association.

Abnormalities, Drug-Induced↗

PubMed2004

Gestational trophoblastic disease: is intensive follow up essential in all women?

OBJECTIVE: To determine the timescale of the registration process for gestational trophoblastic disease and its impact on hCG level at registration and subsequent need for chemotherapy. DESIGN: A prospective observational study using a standardised protocol for registration, assessment and treatment for molar pregnancy. SETTING: A supra-regional tertiary referral centre for gestational trophoblastic disease. PARTICIPANTS: A total of 2046 consecutive women registered between January 1994 and December 1998 with a diagnosis of molar pregnancy. METHODS: Data at and after registration, collected prospectively on a computerised database, were statistically analysed (by multiple logistic regression and ANOVA). MAIN OUTCOME MEASURES: Relationship between length of time to and hCG value at registration; also the subsequent need for chemotherapy. RESULTS: A total of 2046 women with a diagnosis of molar pregnancy were registered in the study period. The mean time interval between first evacuation and registration at the referral centre was 47 days (median 37, range 0-594). One hundred and five out of 2046 (5.1%) women needed chemotherapy. Sixty-three precent of the women (1296 out of 2046) had a normal level of urinary hCG (less than 40 IU/24 hours) at the time of registration and only one (0.08%) needed chemotherapy. Binary logistic regression analysis showed a statistically significant relationship between time to registration, hCG value, histology, pretreatment risk score and decision to administer chemotherapy. CONCLUSION: Women with gestational trophoblastic disease who were registered late were significantly more likely to have normal levels of hCG and were less likely to need chemotherapy. A less intensive follow up may be justified in women with gestational trophoblastic disease who are registered with a normal hCG level.

Adult↗

PubMed1999

Vaginal misoprostol for pre-abortion cervical priming: is there an optimal evacuation time interval?

OBJECTIVE: To determine the optimal evacuation time interval in the use of vaginal misoprostol for cervical priming before first trimester termination of pregnancy. DESIGN: Prospective double-blind randomised study. SETTING: Fertility Control Centre, National University Hospital, Singapore. METHODS: Sixty healthy nulliparous women requesting legal termination of pregnancy between 6 and 11 weeks of gestation were randomly allocated to either the 400 microg or 600 microg misoprostol group. Vacuum aspiration was performed after three hours in the 400 microg group and at the end of two hours in the women given 600 microg misoprostol. Using Hegar's dilator, degree of cervical dilatation before operation was measured. Other parameters assessed included the amount of additional dilatation required (if < Hegar 8), pre-operative and intra-operative blood loss, and associated side effects. RESULTS: For the 600 microg group, only five women (16.7%) achieved a cervical dilatation of > or = 8 mm, compared with 28 women (93.3%) in the 400 microg group. Using the 400 microg misoprostol group as a baseline, the odds ratio was 0.014 (95% CI 0.003-0.080) for 600 microg for successful pre-operative cervical dilatation of > or = 8 mm. The mean cervical dilatation for 400 and 600 microg misoprostol was 8.1 mm and 6.6 mm, respectively (P < 0.001). Despite the shorter evacuation time interval of two hours, the 600 microg dose was associated with an increase in side effects such as vaginal bleeding, abdominal pain and a fever of > 38.0 degrees C. However, other than abdominal pain, no significant differences in the frequency of these side effects were shown. CONCLUSION: Use of 400 microg misoprostol with a minimal evacuation time interval of three hours still appears the optimal dosage and evacuation time for cervical priming before first trimester termination of pregnancy.

Abortifacient Agents, Nonsteroidal↗

PubMed1992

Luteal maintenance in cattle after conceptus death during the first trimester of gestation.

The objectives of this experiment were to evaluate effect of age of the conceptus at death on subsequent interval to estrus and to determine whether prostaglandin F2 alpha (PGF) treatment after induced conceptus death would reduce interval to estrus. Sixty-four beef cows were diagnosed pregnant by ultrasonography between 24 and 50 d of gestation. Nine pregnancy groups were identified; each encompassed a 3-d interval from d 24 through 50 of gestation. Cows were allocated at random within pregnancy group to be treated with colchicine to induce conceptus death. Forty-eight hours after colchicine treatment, conceptus death was verified by ultrasonography and each animal received either saline or PGF. There was no evidence of an effect of age of conceptus at death on the subsequent interval to estrus after either saline or PGF. Interval to estrus after saline was 13.5 +/- .8 d, which was greater (P less than .01) than the 6.2 +/- .8 d after PGF. After saline, the estimate for the linear effect of time on serum progesterone (P4) was -1.32 +/- .36 ng/d and was less (P less than .05) than -2.83 +/- .36 ng/d for cows given PGF. Cows were exposed to fertile bulls at the first postabortion estrus. Pregnancy rates were 37.5% for cows given saline vs 31.3% for those given PGF. These results indicate that interval to estrus after conceptus death between 24 and 50 d of gestation is not affected by the age of the conceptus and can be reduced by PGF treatment.

Animals↗

PubMed2000

Increased susceptibility to malaria during the early postpartum period.

BACKGROUND: Pregnancy is associated with increased susceptibility to malaria. It is generally agreed that this increased risk ends with delivery, but the possible persistence of increased susceptibility during the puerperium had not been investigated. METHODS: From June 1, 1990, to December 31, 1998, we monitored exposure to malaria, parasitemia, and morbidity among the residents of a village in Senegal in which the rate of transmission of malaria was high. In this population we analyzed 71 pregnancies in 38 women from the year before conception and through one year after delivery. RESULTS: Among the 38 women, there were 58 episodes of clinical Plasmodium falciparum malaria during 61,081 person-days of observation. The incidence of malaria was 20.2 episodes per 1000 person-months during the year preceding conception and 12.0 episodes per 1000 person-months during the period from 91 to 365 days after delivery. The incidence of episodes of malaria increased significantly during the second and third trimesters of pregnancy and reached a maximum of 75.1 episodes per 1000 person-months during the first 60 days after delivery. The adjusted relative risk of an episode of malaria was 4.1 (95 percent confidence interval, 1.8 to 9.5) during the first 60 days post partum, as compared with the year preceding pregnancy. The duration of fever during the episodes of malaria was longer and the prevalence and density of asymptomatic malarial parasitemia were significantly higher during pregnancy and the early postpartum period than during the other periods. CONCLUSIONS: Among women who live in areas with high rates of transmission of malaria, the susceptibility to malaria is highest during the second and third trimesters of pregnancy and the early postpartum period.

Adolescent↗

PubMed2002

[Delayed interval delivery in multiple pregnancy--case report and review of the literature].

INTRODUCTION: The incidence of multiple pregnancies is increasing with concomitant increased risk in maternal and fetal complications. Premature rupture of membranes and consecutive premature delivery, especially that of immature babies with very low birth weight is accompanied by a high rate of perinatal morbidity and mortality. OBJECTIVES: This is a case report of a mother with twin pregnancy, who aborted the first fetus at 17 weeks and successfully delivered the second one at 29 weeks of gestation with an interval of 84 days following conservative treatment. METHODS: Review of the literature reports the possibilities of the management of delayed interval delivery. RESULTS: The authors conclude that by the use of tocolysis, antepartum steroid-, and antibiotic prophylaxis the life-expectancy of the retained fetus can be improved. CONCLUSION: After the birth of the first fetus delayed delivery in multiple pregnancies can be successful in selected cases. They advocate it only in well prepared perinatal centers for physically and psychologically balanced patients, who are well informed about the risks and benefits of this trial.

Adult↗

PubMed2000

First trimester exposure to cefuroxime: a prospective cohort study.

AIMS: There are no published studies on the safety of cefuroxime use during pregnancy. We therefore investigated prospectively the possible teratogenic effect of intrauterine exposure to cefuroxime. METHODS: One hundred and six women who received cefuroxime during the first trimester of pregnancy were recruited from three teratogen information centres in Israel. Exposed women were paired for age, smoking habits and alcohol consumption with references being exposed to nonteratogenic antibiotics administered for the same indications. RESULTS: Maternal history, birthweight, gestational age at delivery, rates of live births, spontaneous abortions and fetal distress were comparable among the two groups. Rates of major malformations in the cefuroxime group (3.2%) did not differ from references (2%) (P = 0. 61, relative risk = 1.56, 95% confidence interval 0.27-9.15). There was a significantly higher rate of induced abortions among the cefuroxime exposed women as compared to the references (P = 0.04, relative risk = 3.33, 95% confidence interval 0.94-11.77). CONCLUSIONS: Our data may suggest that exposure to cefuroxime during the first trimester is probably not associated with an increased risk for malformations or spontaneous abortions; however, in light of the small sample size and the broad confidence limits, larger studies are needed to confirm these findings.

Abnormalities, Drug-Induced↗

PubMed1999

Outcomes and health status of socially disadvantaged women during pregnancy.

We sought to examine the health status of disadvantaged pregnant women more broadly and to consider if poor maternal health predisposes a woman to an adverse birth outcome. We surveyed 250 women recruited from six health centers in the greater Boston area during their third trimester. The main predictor variables were maternal physical functioning (PF), emotional health (EH), and overall health status in the month prior to pregnancy. The main outcome variables were the decline of maternal PF and EH during pregnancy and adverse birth outcomes. Mean PF scores fell from 91.9 prior to pregnancy to 63.7 during the third trimester (mean scores transformed 0 to 100, where a higher score represents better health). EH remained unchanged during pregnancy. After adjustment, women with a preexisting medical condition reported a lower PF score prior to pregnancy (87.8 versus 94.5, p < 0.05). Poor PF prior to pregnancy or during the third trimester was associated with an increased risk of preterm labor (odds ratio 2.02, 95% confidence interval 1.03-3.97). This study is the first to employ general health status measures to examine changes in health during pregnancy. Our findings support the use of preconception care to improve the health status of disadvantaged women with pre-existing conditions. This study suggests that poor maternal health may predispose a woman to an increased risk of preterm labor.

Adult↗

PubMed1985

Prospects and limitations of the rosette inhibition test to detect activity of early pregnancy factor in the pig.

After preincubation of lymphocytes in serum of non-pregnant pigs and using a standard anti-pig-lymphocyte serum the upper limit of the 99.9% confidence interval of rosette inhibition titres (RIT) for pig serum was calculated to be 11.4 and all titres greater than 12 were defined as a proof of early pregnancy factor (EPF)-activity. The reproducibility of the RITs with serum samples of pregnant pigs was considered satisfactory (interassay coefficient of variation 23.8%), whereas their reproducibility was considered good with sera taken from non-pregnant animals (interassay coefficient of variation 6.5%). Problems of the test were particularly evident due to the absence of increased RITs after previous incubation of lymphocytes in serum of pregnant pigs. Therefore, all EPF-negative samples were reanalyzed up to two times; pregnancy was then correctly diagnosed for 88.7% of sows. There were 8.6% false positive results (N = 70) and 12.2% false negative results (N = 205). During the first half of pregnancy RITs displayed periodic fluctuations which resembled the physiological cycle interval of the pig. Between Weeks 5 and 9 of pregnancy greater numbers of EPF-negative sows were detected. Subsequently, a continuous increase of mean RITs occurred, which then declined gradually from Day 80 of pregnancy. Similar changes were observed for progesterone values in the dialysed serum samples. However, highest progesterone concentrations always followed elevated RITs with a delay of 1.5-4 days. A subthreshold cyclicity of ovarian and luteal function probably persists despite pregnancy.

Animals↗

PubMed1984

Twin pregnancy: report of a case with 35 days between deliveries.

A prolonged interval between the births of the first and second of twins is rare and only a few reports are found in the literature. This paper reports a patient with twins with an interval of 35 days between the births of the 2 infants, who, due to prematurity and complications, were both stillborn. Three months later the patient became pregnant again and after an uneventful pregnancy gave birth to a healthy baby. However, due to breech presentation an abdominal delivery was undertaken.

Adult↗

PubMed1997

Prenatal smoking in two consecutive pregnancies: Georgia, 1989-1992.

OBJECTIVE: To explore the patterns of prenatal smoking among women whose first and second pregnancies ended in live births. METHODS: We used population-based data to explore prenatal smoking among 14,732 white and 8968 black Georgia residents whose first and second pregnancies ended in live births during 1989-1992. Smoking status was obtained from birth certificates linked for individual mothers. Because of demographic differences, we analyzed white and black women separately. RESULTS: Approximately 15% (2253) of white women and 4% (318) of black women smoked during their first pregnancy. Of those smokers, 69% (1551) of white women and 58% (184) of black women also smoked during their second pregnancy. For both white and black nonsmokers during the first pregnancy, low education was the most significant predictor of smoking during the second pregnancy, after adjusting for consistency of the father's name on the birth certificate, prenatal care, birth interval, mother's county of residence, and birth outcome. CONCLUSIONS: The prevalence of smoking in this study may be low because of underreporting of prenatal smoking on birth certificates. The majority of women who smoked during their first pregnancy also smoked during their second, suggesting that these women exposed their first infant to tobacco smoke both in utero and after delivery. Practitioners should offer smoking cessation programs to women during, as well as after, pregnancy. Pediatricians should educate parents on the health risks to young children of exposure to environmental tobacco smoke and refer smoking parents to smoking cessation programs.

Adolescent↗